Discoloration Control of Light-Colored Wood Caused by Stain Fungi Using Boron and Heat Treatments

Light-colored wood commonly used as a raw material for furniture is often subject to quality deterioration due to the attack of staining fungi. Control methods that may be applied include the use of boron compounds and heat treatment. Therefore, this study aimed to analyze the characteristics of staining fungi attack and evaluate the effectiveness of combined boric acid equivalent (BAE) and heat treatments in reducing the intensity of fungi attack. Preservation was applied to pine and rubber woods using a 5% BAE solution, combined with heating treatments at 60°C, 120°C, and 180°C. The evaluation focused on the intensity of fungi attack, color change, and ultramicroscopic analysis. The results showed that infection by Aspergillus brevipes caused a high degree of discoloration (ΔE > 12). A. brevipes and Aspergillus niger attack wood tissue, specifically in the vessels, by using the pits as an intercellular penetration route. The combination of BAE preservation and heating at 180°C led to a significant increase in wood density and anti-swelling efficiency. This treatment effectively increased the resistance of pine and rubber woods against A. brevipes and A. niger.